Argo Group International Holdings announced plans to merge two of its excess and surplus lines businesses, Argonaut Specialty and Colony, to form Colony Specialty.

A Harrisburg, Pa.-based insurance company had its ratings withdrawn by A.M. Best Co. because it merged into its affiliate, Praetorian Insurance Co.

The Maryland Insurance Administration in December 2009 approved the merger of the Maryland entity of Aetna Health with the Pennsylvania entity of the same name.

The Pennsylvania Insurance Department’s plans to release the first of four reports on competition among the state’s Blue Cross and Blue Shield insurers has hit a legal roadblock.

Donegal Financial Services Corp. announced an agreement to merge with fellow Pennsylvania institution Union National Financial Corp. in a move to enhance its financial service offerings.

AmWINS Insurance Group and Colemont Insurance Brokers are merging, creating a specialty insurance distributor that will place more than $4.8 billon in annual premium.

Highmark Inc., the state’s largest health insurer, is shifting its small-group business to a for-profit entity, which will allow it to consider medical underwriting.

Highmark Inc.’s unfavorable earning trends, forecasted to show little improvement in the coming year or two, led a rating service to revise the health insurer’s credit rating to “negative.”

A pair of Pennsylvania firms are merging in a move they say will bolster the new entity’s market share in the Lehigh Valley and south central regions of the state.

Following a rejection by 21st Century Holding Co. on a possible merger, Homeowners Choice, a Clearwater, Fla., property-casualty insurer, has dropped its bid for the company, but has not ruled out a “hostile acquisition” in the future.